Tire-deflation indicator



C. W. ZIMMERMAN.

TIRE DEFLATION INDICATOR.

APPLICATION FILED I:IAR.9, 1920.

2 SHEETS-SHEET 1.

Patented; D30. 6, H21.

C. W. ZIMMERMAN.

TIRE DEFLATION INDICATOR.

APPLICATION FILED MAR.9, 1920.

Patented Dec. 6, 1921.

2 SHEETS-SHEET 2.

(Ila/MW Zi/IclIzer/m spec1fication.

PATENT OFFICE.

CLARENCE W. ZIMMEIRMAN, OF VENANGO,

JAMES- M. FULTON,

NEBRASKA, ASSIGNOR 0F ONE-HALF TO DIE HOLYOKE, COLORADO.

TIRE-DEFLATION mmcn'ron Specification of Letters Patent.

Patented Dec. 6, 1921.

Application filed March 9, 1920. Serial No. 364,473.

To aZZ whom it may concern:

Be it known that I, CLARENCE W. ZIMMER- MAN, a citizen of the United States, residing at Venango, in the county of Perkins and State of Nebraska, have invented certain new and useful Improvements in Tire-Deflationlndicators, of which the following is a his invention relates to a tire deflation indicator for apprising the driver of a motor vehicle when the ressure in the tire drops below a predetermlned point.

With the usual form of tire valve used in pneumatic tires there is no way of indieating to the driver of the vehicle carrying such tires that the pressure in said tire or tires has become so low as to work injury to the tire if the vehicle is driven further; as a consequence, many tires are ruined b being driven flat or partially deflated before being discovered.

An object of the present invention resides in the provision of a device which will warn the driver of a deflated tire by reason of the fact that the motor power of the vehicle is cut off when such a condition exists, thereby preventing further operation until the device giving this warning is either removed or the condition remedied.

A further object of the invention resides in associating a pressure indicator of the visible indicating type with a tire valve of the usual Schraeder construction in which a plunger valve is depressed for admission or emission of the inflating fluid, such pressure gage being so constructed that when the indicating' member thereof moves to a' predetermined low pressure point a circuit will be closed to interruptthe' ignition in the en ine cylinders of In t e drawings:

Figure 1 is a side elevation of a motor vehicle equipped with the invention.

Fig. 2 is a detail view, in side elevation, showing the associated pressure gage and tire valve;

Fig. 3 is a'xvertival transverse section, partly in elevation as to the axle parts, showing the circuit closing means for the revolving parts of the axle construction;

Fig. 4 is an elevational view of the brake a motor vehicle.

drum and closing cover with the brush mechanism in side elevation.

In detail:

The invention, as herein shown, is embodied in a pleasure vehiclefbut it is equally 'with the ring 11.

tires of the vehicle is applicable to commercial vehicles such as trucks which are rapidly coming to the use of pneumatic tires.

Also, the invention, as shown herein, is applied to rear wheel construction but is equally adaptable to front wheel construction when the necessary inconsequential modifications are made.

The rear wheel of the vehicle is indicated t 1 and carries a pneumatic tire 2 having the usual Schraeder valve 3. Any standard form of tire pressure gage is connected with the valve 3 and is provided with an indicating scale 5 and a pointer 6, said pressure gage being generally indicated by the numeral 4. Fixed to the dial carrying the scale 5 and disposed with respect thereto at a predetermined low pressure point is a contact member 7. -'lhe pointer'6 may move into contact with said contact 7.

The primary wire 8 leading from the ignitioncoil of the vehicle is connected with the brake drum spider 8. Said brake drum spider 8 carries a brush holder 9 insulated from the brake drum spider and having a tension brush .10 maintained in contact with the ring 11 by a suitable spring, said ring 11 being carried by the brake drum but insulated therefrom, as indicated at 13. 'The wire 8, while attached to the brake drum spider 8', has no electrical connection therewith but is established between the brush holder 9. A the contact 7 of the the said wire 8 and wire 8 connects with pressure gage 4 and also The brake drum 12 is included in the ground'of the vehicle ignition system, the source of electrical energy of such ignition system being suitably grounded at any point on the vehicle chassis. Thepointer 6 of the pressure indicator 4 is grounded on the able manner, as indicated at 14. Therefore, when the pressure within the tire tube has fallen to the predetermined oint,'the said pointer 6 crosses the contact and grounds the primary wire 8 through the medium of the wire 8 and the said brush 10, thereby cutting out ignition in the cylinders of the vehicle engine whereby the vehicle is immediately stopped. and cannot be again operated until the tire conditions have been remedied. In this manner damage to the ositively avoided as they cannot be run de .ated. r

I claim:

electrical connection The combination with the ignition system said pressure gage for traversing said conof a pneumatic tired motor vehicle, of a tact and grounded on the vehicle whereby 10 brake drum carrying an insulated ring, a traversing of said contact by such pointer brush bearing on said insulated ring and interrupts the operation of the ignition connected with the primary wire of the system.

. ignition system; a 'pressure gage carried by In testimony whereof I aflix my signature.

each tire and having a contact connected with the sald ring, a pointer embodled in CLARENCE W- ZIMMERMAN- -1 

